Target vibration isolation mount



June 25, 1968 a. 5. DAY ETAL TARGET VIBRATION ISOLATION MOUNT Filed March 16, 1966 Egg K :M 8 R E T o N W W mm IR ATTORNEY.

United States Patent Ofice 3,390,294 Patented June 25, 1968 3,390,294 TARGET VIBRATION ISOLATION MOUNT Bernard E. Day and Wilbur M. Clark, Liverpool, N.Y., assignors to General Electric Company, a corporation of New York Filed Mar. 16, 1966, Ser. No. 534,748 9 Claims. (Cl. 313-67) This invention relates to an improved vibration isolation mounting assembly and more particularly to an improved target vibration isolation mounting assembly as utilized in image orthicon electron image tubes.

In the operation of an image orthicon type camera tube, light falling on a photosensitive surface of the tube produces an emission of electrons which are accelerated axially toward, and impinge upon, a transversely extending charge storage target. The primary electrons arriving at the charge storage target produce emission of secondary electrons which are collected by a closely spaced confronting forarninate or mesh-like electron collector electrode leaving a charge pattern on the storage target which is image representative of the optical image supplied to the photosensitive surface of the tube. The storage information is read out as modulation of the returned current of an electron beam which Scans the storage target.

In image orthicon camera tubes of the type described, even slight and otherwise limited relative motion between the charge storage target and the adjacent electron collector mesh electrode has severe and adverse effects on the quality of a picture or image reproducible from the signal read out from the tube. Such relative motion is usually indicated in the reproduced picture as microphonic bar patterns, which, of course, severely impair the fidelity of the resulting picture. Furthermore, the usual close spaced planar target and planar mesh electrode are frequently supported in drumhead fashion exclusively from an annular or peripheral frame and are therefore quite susceptible to relative movement in an axial direction toward and away from one another when the camera tube is subjected to vibration at frequencies which approach any of those resonant frequencies associated with a target or collector electrode. Reference is made to US. Patent 3,137,803 Ney and US. patent application S.N. 374,672 now Patent No. 3,259,774 Ney, both of which are assigned to the same assignee as the present invention and relate to vibration damping means in camera tubes.

Accordingly, it is an object of the present invention to provide an improved vibration isolation mounting means.

It is another object of this invention to provide improved vibration isolation mounting means which employ a plurality of vibration damping and supporting members periphery positioned about a predetermined periphery between a moving and a fixed system.

It is a further object of this invention to provide an improved vibration damping isolation mounting assembly employing a plurality of vibration damping fibrous members equidistantly peripherally positioned between a surrounding stationary and a moving system on two different sides of the stationary system.

It is a still further object of this invention to provide a vibration damping isolation mounting assemly which employs a plurality of vibration damping fibrous members and flexible tension support members, equally peripherally positioned between a surrounding stationary and a moving coplanar system on opposite sides of the stationary systern.

It is yet another object of this invention to provide an improved vibration isolation system for a target assembly in image orthicon camera tubes wherein metallic fiber members and metal tension strips are positioned between a pair of upstanding flanges of a coplanar system and a single interleaved depending flange.

Briefly described, this invention in one of its preferred forms includes a stationary support member having a radially inwardly directed or depending flange member. An annular target support structure having a pair of radially outwardly directed flange members is concentrically positioned within the annular support member so that the flanges are in spaced interfitting axial relationship. A plurality of fibrous vibration damping material members are equally peripherally positioned between the said flanges, and shear Strips are attached to the target structure near the base of the flanges and to the stationary support member to support the target structure in tension. The target structure is thus supported coaxially within the periphery of the stationary member, and in coplanar relationship therewith.

This invention will be better'understood when taken in connection with the following description and the drawings in which FIG. 1 is an axial sectional view of the image portion of an image orthicon type ofcamera tube,

FIG. 2 is a transverse partially sectional end View of the structure of FIG. 1,

FIG. 3 is an enlarged view of the vibration damping assembly of FIG. 1,

FIG. 4 is a transverse view showing alternate side positioning of the vibration damping means.

Referring now to FIG. 1, there is illustrated a portion of the image end section of a pickup cameras tube 10 of the image orthicon type. Reference is made to U.S. Patents 3,080,094 Ney and 3,090,881 Wellinger, each assigned to the same assignee as the present invention, for further descriptive material of these pickup camera tubes and function relationships of their elements. Tube 10 includes and evacuated envelope 11, having at its forward end a viewing window 12. On the interior surface of the viewing window 12 is a photo-sensitive layer 13 which is responsive to the light image falling thereon. This responsiveness is indicated by electrons being emitted from the layer 13 and accelerated axially or longitudinally by an annular accelerating electrode 14 and an annular isolation cup electrode 15 to a transverse planar member like electric charge storage target 16. The primary electrons impinging the charge storage target 16 produce emission secondary electrons which are then collected by a mesh-like electron collector electrode 17 disposed in closely spaced and confronting relationship with the forward face of the target 16. An electrical charge pattern is thus formed on the charge storage target 16 which is representative of the light image falling on the photoemissive layer 13.

Referring now to FIG. 3, the isolation cup support 15 is a peripheral and preferably annular support member having a radially inturned flange 18 at one end thereof. Depending on the particular needs and design of the tube 10, the electrode 15 and the depending flange 18 may be peripherally or axially coextensive surfaces or composed of a plurality of surfaces electrically cooperative to provide the desired results. For example, as illustrated flange 18 is a separate member suitably attached to isolation cup 15.

The target and collector electrode frame assembly 19 includes a peripheral and preferably annular member 20 having a pair of radially outwardly directed parallel flanges 21 and 22. As illustrated, assembly 19 may comprise a pair of angled annular members suitably joined to provide the parallel pair of flanges 21 and 22. An annular section 23 is suitably attached to member 20 to serve as an engaging member for the target support. Frame assembly 19 is adapted to contain or receive a combined target and collector electrode support unit 24 which is illustrated in FIG. 1. Unit 24 is releasably secured concentrically with member 20, on frame assembly 19, and includes a push-in type cup 25 which fits through member 20 and engages section 23. Cup 25 also carries therewithin a storage target 16 and collector mesh electrode 17. The frame assembly 19 constitutes a movable member or assembly while the isolation cup electrode 15 constitutes a stationary or fixed member or assembly. The vibration damping means of this invention is applied between the mentioned movable and fixed members 15 and 19 respectively.

More particularly, the annular member 19 is concentrically positioned within isolation cup electrode 15 so that upstanding flanges 21 and 22 are in confronting and close spaced axial relationship to depending flange 18 of member 15. In order to support frame assembly 19 in its desired position and to prevent rotational movement thereof, shear strip tension support means are employed. At the base of each flange and on corresponding sides thereof, a thin metallic shear strip 25 is joined to frame assembly 19 for example by first being joined to a rod section and welding the rod section to frame 19. These shear strips are then similarly joined to isolation cup 15 in generally parallel relationship. Best results have been obtained with Nichrome shear strips 25' of 0.001 to 0.002 inch thickness and about 0.125 inch width.

A substantial number of and arrangement of strips 25 may be employed for either the front or rearward position. It is preferred to have single strips 25 equally peripherally spaced in the defined annular space between flanges 18 and 21, and the defined peripheral space rearwardly of flange 22. However, the number of strips in each position may be different and they may be in different angular or peripheral locations. The strips 25 may also be located in a number of other positions between cup 15 and frame 19 on either side of any of the three flanges 18, 21 and 22. In one preferred form of this invention as illustrated in FIGS. 1 and 3, four equally peripherally spaced strips 25 are employed in the described annular space. A further four strips 25 (not shown) are positioned directly opposite the front strips, in the described peripheral space, at the side of flange surface 22 which is remote from depending flange surface 18. These latter shear strips are similar in all respects to the other described shear strips except that they are slightly longer and do not require a rod connection to cup electrode 15. If desirable, however, each pair of opposing shear strips may be attached so that they are in axial angular or intersecting relationship to each other in their fore and aft parallel planes or intersecting planes.

A vibration clamping material member 26 is interposed between flanges 18 and 21 and flanges 18 and 22 to complete a vibration damping unit.

The vibration damping material of member 26 in one form of this invention comprises a material having high internal inherent friction damping characteristics. It is a particular feature of this invention that the vibration damping material should have not only the desired mechanical properties for vibration and shock attenuation, but also to be compatible with the stringent requisites of a high vacuum image orthicon tube environment, in which the target collector assembly is intended to operate. The particular feature to be taken into consideration for a choice of the vibration damping material is the presence of the metal cesium or cesium vapor in image orthicon tubes. The adverse effects of this metal vapor on various materials in the tube is well known so that where this metal is so employed, the choice of vibration damping material is limited. Furthermore, the vibration damping material must be one of those materials having a sufliciently low vapor pressure or low capacity for occluded gases to avoid appreciable outgassing during tube opera tion. Suitable materials which will provide proper vibration damping in the practice of this invention are, for example, stainless steel, Monel metal, certain glasses, quartz, and other non-metallic materials. More particularly, in the practice of this invention, the vibration damping material preferably comprises a material of high internal friction damping characteristics such as bundles of fibers or strands of intertwined, interwoven, or resilient wool-like masses, pads, rolls, of metal. Preferred examples are suitably formed steel wool and metal braid. For example, in one working embodiment of this invention, the damping material was of .002 diameter Iconel 600 wire which was interwoven in the form of a tubular or hose configuration and of approximately 0.5 inch length.

Member 26 may be suitably contained between flange 18, 21 and 22 so that relative motion therebetwecn is transmitted through the interwoven material of member 26. In one preferred form of this invention, a member 26 in the form of an interwoven tubular strip as described is suitably generally peripherally attached to one flange such as flange 18 for example by tack welding, brazing, et cetera. In attaching members 26 to flange 13 the ends of members 26 are closed so that the members are rounded or tube form to project outwardly into engage ment with flange 22. Longer lengths of members 26 may require additional welds to maintain arcuate form along a flange. Other kinds of members 26 may be of substantial thickness or attached in a bunching manner for suitable engagement. As illustrated in FIG. 4, four members 26 are employed equally peripherally spaced and in the same fore and aft plane with strips 25 in the space between flanges 18 and 22. Also, as illustrated in phantom in FIG. 4, a further four members 26 are positioned in the space between flanges 18 and 21 and also secured to flange 18. One or more of all members 26 may also be secured to any of the flanges 18, 21 and 22.

In defining a pair of adjacent surfaces with an intermediate vibration damping material in accordance with the teachings of this invention, those flange and tab surfaces and their supporting structures may be coextensively annular as illustrated for members L8 and 21, for example, or may take separate or singular tab form. In either event these surfaces define a general peripheral or annular arrangement. It is only necessary that a minimum of three damping means he provided on each side of a flange member, i.e., at least three suspension strips 25 and preferably three damping members 26. The three vibration damping means of this invention may be applied to various other target support and electrode combinations of various configurations and broadly to charge storage target fixation per se. The particular embodiment illustrated and described is particularly adaptable to image orthicon tubes.

A vibration isolating target mounting structure constructed as described is found to be extremely effective in preventing movement of the charge storage target relative to the collector electrodes at frequencies as have heretofore produced undesirable effects in the picture or other image produced from the output signal of the tube. Moreover, such a vibration damping mount permits extended damping movement of the target collector electrode assembly at low frequencies below the frequency of the resonance of the target or mesh electrode so as to preclude rupture or other injury to the target or mesh electrode when the tube is subjected to low frequency vibrations. It will be evident that such a mounting arrangement as herein described provides effective protection or ruggedization of the tube against the deleterious effects of vibration and enables continued operation of the tube with desirable picture quality under extremely adverse vibrational conditions.

It will be appreciated by those skilled in the art that this invention may be carried out in various ways in addition to that described, and may take various forms and embodiments other than those illustrated. Accordingly, it is to be understood that the scope of this invention is not limited to the details of the foregoing description but will be properly defined in the following claims.

A singular advantage of this invention lies in the use of a single depending flange on the stationary system and plural upstanding flanges on the moving system. This configuration includes the use of pairs of spaced shear strips for supporting assembly 19. The overall arrangement simplifies both the structure and assembly of component parts as well as increasing vibration damping by the supporting means. A further advantage is the minimal axial dimension required for this vibration damping unit in image orthicon and other camera tubes where axial space is at a premium. The outstanding advantage of this invention which is related to the foregoing advantages is the suspension of the target 16 within the periphery of the annular support system. This pendulum-like arrangement places the target or moving system mass in general balanced relationship with the vibration damping means in a substantially coplanar manner. Consequently the vibration forces associated with cantilever and the like supports are substantially diminished as illustrated in FIG. 1. Cup 24 includes a shoulder 27 at one end and a stop surface 28 at the other end. Cup 24 is slidabl-y positioned in the aperture defined by annular member 20 until positioned by engagement of shoulder 27 with annular member 20 and stop 28 with section 23. In this position, the plane of target 16 passes between upstanding flanges 21 and 22 for a generally coplanar pendulumlike supporting relationship.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A television camera tube electrode supporting means comprising in combination (a) an annular support member,

(b) an annular frame assembly Within said support member,

(c) flange surfaces on said frame assembly and said support member interleaving with each other,

(d) a plurality of coplanar flexible tension strips about the periphery of said support member on one side of one of said flanges surfaces and attached to said frame assembly for support thereof,

(e) a plurality of coplanar flexible tension strips about the periphery of said support member on the other side of said one flange surface,

(f) a plurality of coplanar vibration damping masses on one side of and engaging said one of said flange surfaces and an opposed flange surface,

(g) a plurality of coplanar vibration damping masses on the other side of and engaging said one flange surface and an opposing flange surface,

(h) said frame supported axially and peripherally within said support member transversely in pendulum-like coplanar relationship,

(i) so that relative motion between said frame and said support is transmitted through said vibration damping means and said tension members for damping of said .motion.

2. In an image orthicon camera tube a vibration damping target support therefor comprising in combination (a) a first fixed peripheral defining electrode support having a depending surface,

(b) a movable target containing frame assembly having a pair of upstanding surfaces in interleaved and spaced relationship with said depending surface,

(c) said target being suspended within the peripheral relationship of said support,

((1) at least six strip members attached adjacent the base of each said upstanding surface and to said first fixed support to support said movable frame in tension,

(e) three of said strip members being peripherally spaced between one of said upstanding surfaces and said depending surfaces,

(f) three of said strip members being peripherally I spaced between the other of said upstanding surface and said depending surface, and

(g) at least six vibration damping fibrous pads being peripherally positioned about said movable frame for vibrational isolation thereof,

(b) three of said fibrous members being positioned between and engaging said depending surface and one of said'upstanding surfaces,

(i) three of said fibrous members being positioned between and engaging said depending surface and the other of said upstanding surface,

(j) so that motion of said frame is transmitted through said strips and said fiber members for vibration damping thereof.

3. The invention as recited in claim 2 wherein (a) said fibrous mass is metal,

(b) said tension strips are metal,

(c) said tension strips are arranged in pairs,

((1) the tension strips in each pair being in opposed relationship to each other on opposite sides of said depending surface,

(e) said metal fiber masses on one side of said depending surface being rotatably displaced from the metal fiber masses on the other side of said depending surface.

4. The invention as recited in claim 3 wherein each said pairs of strips and said metal fiber masses are peripherally equally spaced from each other.

5. The invention as recited in claim 3 wherein four tension strips and four metal fiber members are employed on each side of said depending surface.

6. The invention as recited in claim 3 wherein said tension strips angularly approach the plane of the target to support said moving frame in tension.

7. The invention as recited in claim 2 wherein said metal fiber masses are attached to at least one of said surfaces.

8. The invention as recited in claim 2 wherein said metal fiber masses are interwoven ,rnetal members attached to said depending surface and projecting into rubbing engagement with an adjacent surface.

9. In an image orthicon camera tube vibration isolation means for a target assembly comprising in combination (a) an annular control electrode support having a depending flange surface,

(b) an annular frame charge storage target support having a pair of radially outwardly directed flange surfaces in interleaved and axially spaced relationship to said depending surface,

(c) said target support frame and target therein being positioned concentrically within said control electrode with said flanges in close spaced axial relationship and said target being substantially coplanar between said upstanding flanges,

(d) at least eight tension strips of metal attached to the base of said flanges and to said annular control electrode to support said target support in tension,

(e) said strips being equidistantly peripherally positioned at spacings,

(f) four of said strips peripherally positioned between said depending flange and one of said upstanding flanges, I

(g) four of said strips being peripherally positioned on the side of the other upstanding surface remote from the said depending surface,

(h) opposed pairs of said strips being coplanar,

(i) four metal fiber vibration damping masses equally peripherally spaced between and engaging said depending surface and one of said upstanding surfaces,

(j) four metal fiber vibration damping masses equally peripherally spaced between and engaging said depending surface and the other of said upstanding surfaces,

(k) said target frame defining a central aperture References Cited adapted to receive a cup and target therein and UNITED STATES PATENTS (1) means assoeiated with said aperture and said cup 2,661,437 12/1953 Backers X to position said target so that its plane intersects the r 3,137,803 6/1964 Nay et a1 X space between said upstanding flange surfaces, 0 3,259,774 5/1966 Nay 313M269 X (m) so that vibratory motion of said cup is transmitted through said metal fiber masses and said tension JOHN HUCKERT Pfimary Examinerstrips for vibration damping. A. J. JAMES, Assistant Examiner. 

1. A TELEVISION CAMERA TUBE ELECTRODE SUPPORTING MEANS COMPRISING IN COMBINATION (A) AN ANNULAR SUPPORT MEMBER, (B) AN ANNULAR FRAME ASSEMBLY WITHIN SAID SUPPORT MEMBER, (C) FLANGE SURFACES ON SAID FRAME ASSEMBLY AND SAID SUPPORT MEMBER INTERLEAVING WITH EACH OTHER, (D) A PLURALITY OF COPLANAR FLEXIBLE TENSION STRIPS ABOUT THE PERIPHERY OF SAID SUPPORT MEMEMBER ON ONE SIDE OF ONE OF SAID FLANGES SURFACES AND ATTACHED TO SAID FRAME ASSEMBLY FOR SUPPORT THEREOF, (E) A PLURALITY OF COPLANAR FLEXIBLE TENSION STRIPS ABOUT THE PERIPHERY OF SAID SUPPORT MEMBER ON THE OTHER SIDE OF SAID ONE FLANGE SURFACE, (F) A PLURALITY OF COPLANAR VIBRATION DAMPING MASSES ONE ONE SIDE OF AND ENGAGING SAID ONE OF SAID FLANGE SURFACES AND AN OPPOSED FLANGE SURFACE, 